Peripheral Neuropathy on Lorlatinib

Six months in, the patient reports tingling in his fingertips. It is not painful, but he notices it when buttoning a shirt. That detail, a specific task rather than a symptom score, is what makes neuropathy actionable.

Written by Katrina Metz, RT·Medically reviewed by Dr. Geoffrey Liu, MD MPH·Last updated

Key Takeaways

  • Peripheral neuropathy is a common adverse event on lorlatinib, mostly Grade 1-2.
  • Median onset: 2 to 4 months. Median duration: 8 to 18 months.
  • Severe events are less frequent, and incidence does not increase over time.
  • Neuropathy often begins subtly and can persist if ignored.
  • Assessment should centre on functional impact rather than symptom presence.

Table of Contents

Understanding the Pattern

Neuropathy on lorlatinib shares its timeline with peripheral edema: onset at two to four months, duration of eight to eighteen months, and most events at Grade 1 or 2. Severe events are less frequent, and incidence does not climb over time.

The distinguishing feature is how it presents. Neuropathy begins subtly, as a tingling that is easy for the patient to dismiss and easy for the clinician to miss if the question is not asked directly.

Key message: Neuropathy often begins subtly and can persist if ignored.

Recognition and Functional Impact

The most useful clinical questions are about tasks, not sensations. Buttoning a shirt, handling coins, using a keyboard, feeling the floor when walking. These give a measurable read on whether the neuropathy has crossed from noticeable to limiting.

That framing also gives the patient a concrete way to report change between visits.

Practical Interventions

The objective is continuation of therapy at an effective dose. Interventions escalate with functional impact, following the same ladder used elsewhere in the series. Where neuropathy is clearly treatment-related, dose modification should occur before specialist referral.

Frequently Asked Questions

What is the PMMR framework?
PMMR stands for Prepare, Monitor, Manage, Reassess. It is a practical framework for managing lorlatinib's adverse effects, developed by Dr. Geoffrey Liu and colleagues and published in Lung Cancer (2024). Prepare means setting expectations with the patient before the first dose. Monitor combines laboratory values and patient report. Manage means responding in proportion to functional impact. Reassess means confirming the intervention worked and checking for new issues. It is a continuous cycle rather than a one-time checklist. Related: Video 1: PMMR and the Foundations of ALK+ Patient Management
What is the recommended starting dose of lorlatinib?
The recommended starting dose is 100 mg daily. Clinical guidance is to begin at full dose unless contraindicated. Early adverse events are common but often manageable, and starting at full dose maximises initial disease control. Related: Video 8: Dosing and Dose Modification Strategies
Does reducing the dose of lorlatinib compromise its effectiveness?
No. Dose reduction in the early weeks did not compromise progression-free survival or intracranial outcomes. Structured reductions go from 100 mg to 75 mg daily, and to 50 mg daily if a second reduction is required. Dose reduction is part of long-term management, not treatment failure, and this should be stated explicitly to patients. Related: Video 8: Dosing and Dose Modification Strategies
How often should lipids be monitored on lorlatinib?
A baseline lipid profile, a recheck at one month, two months and then every 3 months. Onset of lipid changes is approximately 15 days, which is why the two-week check matters. Trend over time is more informative than any single value. Related: Video 7: Hyperlipidemia and Metabolic Effects
Which statins are preferred in patients on lorlatinib?
Pitavastatin, pravastatin and rosuvastatin are preferred, selected on the basis of their drug interaction profile. If control is inadequate, ezetimibe can be added, and a fibrate or fish oil for triglycerides. Diet alone is rarely sufficient, and dose reduction of lorlatinib is rarely required for lipids alone. Related: Video 7: Hyperlipidemia and Metabolic Effects
How common are adverse events on lorlatinib?
Most adverse events are Grade 1 or 2. Hypercholesterolemia occurs in approximately 70 to 75 percent of patients and hypertriglyceridemia in approximately 60 to 65 percent. Weight gain occurred in approximately 44 percent of patients in long-term CROWN follow-up. Peripheral edema, peripheral neuropathy and CNS effects are also common, with median onset of two to four months. For most events, incidence does not increase over time. These are CROWN long-term follow-up figures rather than a global average. Related: Video 2: Weight Gain · Video 3: Peripheral Edema · Video 4: Peripheral Neuropathy
What CNS side effects can occur with lorlatinib, and are they reversible?
CNS adverse events include changes in mood, cognition and speech. Most are Grade 1 to 2, with median onset at two to four months, and discontinuation rates are very low. These changes are often early and reversible with structured intervention. The main clinical risk is delayed recognition rather than the severity of the event, which is why caregiver input is valuable. Changes are frequently noticed by a family member before the patient reports them. Related: Video 5: Cognitive and Mood Changes
Should therapy be switched if there is isolated CNS progression?
Not automatically. If progression is intracranial only, confirm the imaging, assess symptom burden, consider local therapy, and continue CNS-active systemic therapy where appropriate. Time to intracranial progression is significantly prolonged with lorlatinib, and dose reduction does not compromise intracranial efficacy. Therapy should not be switched reflexively for limited CNS progression. Related: Video 9: Sequencing After Progression · Video 6: Brain Metastasis
When should a patient on lorlatinib be referred to a specialist?
Refer when function, safety, or disease control is at risk. Neurology or psychiatry for functional cognitive impairment, behavioral instability, safety concerns, or persistent CNS toxicity despite dose adjustment. Cardiology or a lipid clinic when lipids remain uncontrolled despite maximal statin therapy, or where there is statin intolerance or complex cardiovascular risk. Radiation oncology or a tertiary centre for isolated CNS progression or symptomatic lesions. Central oncologic oversight should be maintained throughout. Related: Video 11: When to Refer to a Specialist
How often should patients on lorlatinib be followed up?
Biweekly during the first month, monthly for three months, and every three months thereafter. After any treatment interruption, return to biweekly reassessment. A standardised adverse event checklist at each visit, screening for weight change, edema, neuropathy, and mood or cognition, improves detection compared with open-ended questioning. Related: Video 10: Clinical Tools for Monitoring and Follow-Up

This content is intended for healthcare professional education and reflects clinical guidance current at the time of publication. It is not a substitute for the product monograph, institutional protocols, or individual clinical judgement.

Stay Informed

RESPIPLUS publishes free, evidence-based education for Canadian healthcare professionals across chronic lung diseases, including new videos, clinical guides and podcast episodes, with no paywall and no cost.

Subscribe to RESPIPLUS updates →

This video is one of twelve in Managing Lorlatinib in ALK+ NSCLC, developed with Dr. Geoffrey Liu and the CARMA-BROS network at Princess Margaret Cancer Centre.

Watch the full series →  ·  Explore the Lung Cancer Hub →

Continue the Series

Related Resources

About this article

Written by Katrina Metz, RT, respiratory therapist and medical writer at RESPIPLUS. Medically reviewed by Dr. Geoffrey Liu, MD MPH, Senior Scientist at Princess Margaret Cancer Centre and a leading Canadian expert in ALK-positive NSCLC management.

About this project
This series was supported by Pfizer and developed independently by RESPIPLUS with the CARMA-BROS network. Scientific Committee: Dr. Geoffrey Liu (Princess Margaret), Maria Sedeno (RESPIPLUS), Emily Horvat (RESPIPLUS), Katrina Metz (RESPIPLUS), Christopher Deutschman (CARMA-BROS), Faisal Al Agha (CARMA-BROS). All materials are free and permanently hosted on chroniclungdiseases.com.

Published August 4, 2026. Last reviewed . For educational purposes only. Not a substitute for medical advice.